Twin-bucket excavator.



IATENTED DEC. 11 G. G. JACOBS.

TWIN BUCKET EXGAVATOR.

APPLICATION FILED APE-14.1906.

3 SHEETS-SHEET 1.

PATENTED DEC. 11, 1906.

0. 0. JACOBS. TWIN BUCKET EXGAVATOR.

APPLICATION FILED APB.14.1906.

3 SHEETS-SHEET 2.

No. 838,335. PATENTED DEC. 11, 1906.

Q G. O. JACOBS.

TWIN BUCKET BXOAVATOR.

APPLICATION FILED APR. 14.1906.

3 SHEETS-SHEET 3.

n1: NORRIS PETERS 5a., wuumarcn, n. c.

UNITED STATES PATENT oEEIGE.

CHARLES C. JACOBS, OF CHICAGO, ILLINOIS, ASSIGNOR TO F. C. AUSTIN DRAINAGE EXCAVATOR COMPANY, OF CHICAGO, ILLINOIS, A CORPO- RATION OF ILLINOIS.

TWIN-BUCKET EXCAVATOR.

Specification of Letters Patent.

Patented Dec. 11, 1906.

To all whom it may concern.-

Be it known that I, CHARLES C. JACOBS, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Twin-Bucket Excavators, of which the following is a specification.

In order to provide a bucket mechanism for use in an excavator which shall shave ofi' a layer of earth when traveling in both directions, being operated on a track shaped to conform substantially to the cross-sectional profile of the trench or ditch to be dug, I have invented a twin or double bucket device which comprises a truck adapted to reciprocate on the track and two buckets or scoops with cutting edges facing each other, the scoops being preferably pivoted to the truck and having their mouths overlapped or partly telescoped. By using a suitable type of track all the dirt removed from the trench may be dumped on one bank to form a levee or it may be discharged on both banks, if desired. By employing a two-bucket device of this character I am enabled to remove from the trench a greater load of dirt on a single reciprocation of the truck and attached buckets than is possible in an excavator employing a single bucket.

In the accompanying drawings I have illustrated my improved double bucket and an excavating-machine inivhich such buckets may be used.

Figure 1 of said drawings is a side elevation of the double bucket, partly in section. Fig. 2 is a cross-section of the bucket shown in Fig. 1 on the line 2 2. Fig. '3 is a plan view of the double or twin bucket, and Fig. 4 is an elevation of an excavator employing a bucket of my improved type.

The truck of the double bucket comprises two longitudinal channel-bars 10 10, spaced apart and tied together at their two ends by the top channels 11 11. At the forward and rear ends of the truck there is provided a shaft 12, having the wheels or rollers 13 at its extremities. Across the truck and near its two ends are shafts 14, and on each of these I pivotally mount two side-plate members 15 adjacent to the channels 10, eachof the plates 15 having an outwardly-extended marginal flange 16, adapted to overlap the top flange of channel 10 and limit the downward turning of the plate on the shaft. Each pair of plates 15 is cross-connected by a bar 17, riveted to the flanges 16. The ends of plates 15 near the shaft arew transversely connected by two angle-bars 18, which at their outer ends are riveted to other anglebars 19, fastened to the side plates 15. Depending from each of the plates 15 is a bearing plate 20, the two pairs of plates 20 supporting shafts 21, on which are mounted twin buckets 22. Each of these shovels or scoops 22 has a rounded surface 23 and a sharp cutting edge 24, the front mouths of the buckets overlapping or partly telescoping, as is shown in Fig. 1. Extended across the top edge of each bucket is a plate or bar 25, having a pair of upwardlyprojecting lugs 26, to which are attached cables 27 and 27 The buckets are so mounted that unless held in horizontal position they will naturally turn on their pivots to discharge their contents, and to maintain them in load-retaining position I provide for each bucket two sliding catches 28, reciprocating through slots in the upstanding flanges of angle-bars 18. Angle-bars 29 connect these pairs of catches, and in order to project them so as to engage the top surfaces of the buckets I provide for each pair of catches an elliptic spring 30, placed between the upright flanges of bar 29 and bar 18, nearest the end of the truck. To retract these pairs of latches 28, I equip each shaft 14 with two arms 31, and at the end of the shaftI provide another arm 32. The arms 31 extend into slots in catches 28, and as the shaft 14 is turned by its arm 82 the catches 28 may be slid backward, so as to allow the bucket to turn on its pivot and discharge its load.

In order that both buckets may be unloaded at the same time, I mount a lever 33 at the center of one of the channels 10, pivoting the same at 34, and connect this lever by links 35, attached thereto on opposite sides of pivot 34 to the arms 32. By swinging the trip-lever 33 one way or the other the latches may be brought into inoperative or operative position; but the springs normally force them into bucket-engaging position.

The buckets are pivotally mounted on the shafts 14in order that they may ride over any irregularities on the surface of the ground when they are moved backward but when the bucket travels forward its cutting edge slices off a layer-of dirt, as will be obvious, its companion bucket rising sufficiently to ride over the dirt which the trailing bucket shaves off. In Fig. 4 I have illustrated an excavator of a type in which my double bucket may be used. An excavator of this general character has been set forth in my Reissue Patent No. 12,441, of January 30, 1906, and to this IO patent reference is made for the details of the excavator. Briefly stated, the excavator comprises a main skeleton or open-work frame 36, equipped with rollers 37, adapted itotravel on temporary rails 38, laid along the I5 side of and parallel to the trench to be dug. Vertically adjustable within this main fraire is atrack-frame 39, comprising two templet or-" t1 -ack plates 40, the central portions of i which are shaped to conform substantially to the cross-sectional profile of the trench. Each track-plate has upwardly-divergent legs'41, communicating with suitably-supported substantially horizontal extensions 42. Each track-plate also has upper and 25 lower angle-bars 43 and 44, respectively, which cooperate with the wheels of the bucket-truck when the latter reciprocates on the track as it is intended to do. On a platform of the main frame 36 is a 0 boiler and engine 45 to rotate a drum 46, on which may be wound and paid out the cables 27 and 27 which at their free ends are attached to the buckets or scoops, as shown in Fig. 1. Cable 27 passes from drum 46 to 3 5 the angularly-disposed guide-pulleys 47, thence to the pair of sheaves 48, and then around the sheaves or rollers 49 and 50 on the vertically-adjustable track. Cable 27 passes around similar sheaves and pulleys 51, 52, 40 53, and 54. Near the lower portion of frame 39 are pulleys or rollers 55, which coact with both of the cables 27 and 27, which alternately pass beneath the same.

As the double bucket or shovel is recipro- 45 cated on this track from one horizontal ex tension 42, down the incline 41, across the horizontal portion 40, and up the opposite incline onto the opposite horizontal extension the forward scoop or shovel is idle and 5 0 rides over the layer of dirt scraped off by the rear scoop. Then as the double bucket traverses the track in the opposite direction the scoop which was idle on the former trip now becomes active, while the former active scoop becomes idle. WVhen the buckets reach the horizontal extensions 42, they are tripped either manually or automatically so as to discharge their contents, and then when the,

cables are again pulled tight the buckets are brought to load-retaining position, where they are held by the sliding catches.

It will be obvious that the dirt removed from the trench might be discharged so as to form an embankment on each side of the ditch or only on one side, as the case requires.

When the dirt is only dumped on one bank, the double bucket does not need to travel on the horizontal extension over the opposite bank.

Various mechanical changes or modifications of the structure set forth above and illustrated in the drawings are included within the scope of my invention as defined by the appended claims.

I claim 1. A double shovel for use in an excavating-machine, comprising a support, and two sharp-edged buckets mounted on said support with their mouths facing each other, substantially as described.

2. A double shovel for use in an excavating-machine, comprising a support, and two sharpedged buckets pivotally mounted on said support with their mouths facing each other, substantially as described.

3. A double shovel for use in an excavating-machine, comprising a truck, and two sharpedged buckets mounted on said truck jwith their mouths facing each other, substantially as described.

4. A double shovel for use in an excavating-machine, comprising a truck, and two sharpedged buckets pivotally mounted on said truck with their mouths facing each other, substantially as described.

5. A double shovel for use in an excavating-machine, comprising a truck, and two sharp-edged buckets pivotally mounted on said truck with their mouths facing and overlapping each other, substantially as described.

6. A double shovel for use in an excavating-machine, comprising a truck, a pair of buckets pivotally mounted on said truck, a: catch for each bucket to maintain it in loadretaining position, and means connecting said catches enabling them to be simultaneously operated thereby permitting the buckets to discharge their contents at the same time, substantially as described.

7. In an excavator, the combination of a track, a truck adapted to reciprocate on said track, and a pair of buckets each with a cutting edge mounted on said truck with their cutting edges facing each other, substantially as described.

8. In an excavator, the combination of a track a portion of which is shaped to conform substantially to the cross-sectional profile of the trench to be dug, a truck adapted to re ciprocate on said track, and a pair of buckets with cutting edges pivoted to said truck with their cutting edges facing each other, sub stantially as described.

Signed by me at Chicago this 7th day of April, 1906, in the presence of two witnesses.

CHARLES C. JACOBS.

l/Vitnesses:

FREDERICK O. GooDwIN, WALTER M. FULLER. 

